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The “Great Blue Hole” is the world’s biggest ocean sinkhole and was originally formed from a vertical cave in the last glacial period. The prehistoric dry cavern formed the site through the dissolution of limestone rocks.
The giant stalactites, dripstone sheets, and columns in the cave show a period of extreme drought during the 10th century. It has become the prove of the Maya civilization between 800 and 1,000 BC collapsed.
A geological process transformed the “Great Blue Hole” when rising sea levels flooded the cave, causing it to collapse and form a large hole in the middle of the sea.
This site, situated near the center of Lighthouse Reef, is 100 kilometers off the coast of Belize in Central America. It has a surface area of 70,650 square meters, a circular shape measuring 318 meters in diameter, and a depth of 125 meters.
It is very safe to swim, dive, or navigate this site with a ship or boat, but always maintain a safe distance due to its oceanic depth.
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The Magical Sea with Underwater Animals
The sinkhole is known for its depth and serves as a rich habitat for various underwater animals living at depths greater than 100 meters.
The underwater animals are giant groupers, neon gobies, Pederson’s shrimp, mollusks, corals, and many more.
The enchanting aura and the crystal-clear waters reveal the inner beauty of this colossal oceanic sinkhole.
This has led “Great Blue Hole” to become part of the Belize Barrier Reef System and a UNESCO World Heritage Site.
The Dangerous Depths of the “Great Blue Hole”
Behind the nature’s beauty, there are mysteries and histories that need to be revealed.
Over the years, the divers have uncovered various artifacts while collecting samples. They can typically dive to a depth of 40 meters due to the low oxygen layer at the bottom.
In 1971, the renowned undersea explorer Jacques Cousteau embarked on an expedition with his ship, the Calypso. It brought fame to this site, eventually ranking it among the top 10 scuba diving destinations.
Besides that, British diver and author Ned Middleton, who resided in Belize for six months, coined the name “Great Blue Hole.”
In 2018, the Aquatica crew descended to the bottom of the Giant Blue Hole. Their mission was to create a 3D map of the interior using sonar scanning from submarines.
Instead of obtaining a clear view, they discovered unexpected items at these depths, including trash that had reached the ocean’s depths.
There are two-liter Coke bottle at 407 feet and a GoPro camera filled with someone’s vacation photos.
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Unusual Pathways and the Uncovering of Deceased Individuals
Moreover, they encountered a thick layer of toxic hydrogen sulfide that hindered oxygen from reaching deeper into the sinkhole.
Farther below the surface of the Great Blue Hole, a hushed darkness prevailed. The divers stumbled upon the final resting site of two lost fellow divers within the abyss.
The main reason behind the discovery of the bodies of two missing divers may be the danger associated with this depth. The expedition crew laid them to rest at sea and reported the incident to Belizean authorities.